3,011 research outputs found
Peer to Peer Networks Management Survey
Peer-to-Peer systems are based on the concept of resources localization and
mutualisation in dynamic context. In specific environment such as mobile
networks, characterized by high variability and dynamicity of network
conditions and performances, where nodes can join and leave the network
dynamically, resources reliability and availability constitute a critical
issue. The resource discovery problem arises in the context of peer to peer
(P2P) networks, where at any point of time a peer may be placed at or removed
from any location over a general purpose network. Locating a resource or
service efficiently is one of the most important issues related to peer-to-peer
networks. The objective of a search mechanism is to successfully locate
resources while incurring low overhead and low delay. This paper presents a
survey on P2P networks management: classification, applications, platforms,
simulators and security.Comment: 10 pages, 1 figur
Survey of Search and Replication Schemes in Unstructured P2P Networks
P2P computing lifts taxing issues in various areas of computer science. The
largely used decentralized unstructured P2P systems are ad hoc in nature and
present a number of research challenges. In this paper, we provide a
comprehensive theoretical survey of various state-of-the-art search and
replication schemes in unstructured P2P networks for file-sharing applications.
The classifications of search and replication techniques and their advantages
and disadvantages are briefly explained. Finally, the various issues on
searching and replication for unstructured P2P networks are discussed.Comment: 39 Pages 5 Figure
Analysis of the flooding search algorithm with OPNET
In this work, we consider the popular OPNET simulator as a tool for
performance evaluation of algorithms operating in peer-to-peer (P2P) networks.
We created simple framework and used it to analyse the flooding search
algorithm which is a popular technique for searching files in an unstructured
P2P network. We investigated the influence of the number of replicas and time
to live (TTL) of search queries on the algorithm performance. Preparing the
simulation we did not reported the problems which are commonly encountered in
P2P dedicated simulators although the size of simulated network was limited
Query Routing and Processing in Peer-To-Peer Data Sharing Systems
Sharing musical files via the Internet was the essential motivation of early
P2P systems. Despite of the great success of the P2P file sharing systems,
these systems support only "simple" queries. The focus in such systems is how
to carry out an efficient query routing in order to find the nodes storing a
desired file. Recently, several research works have been made to extend P2P
systems to be able to share data having a fine granularity (i.e. atomic
attribute) and to process queries written with a highly expressive language
(i.e. SQL). These works have led to the emergence of P2P data sharing systems
that represent a new generation of P2P systems and, on the other hand, a next
stage in a long period of the database research area. ? The characteristics of
P2P systems (e.g. large-scale, node autonomy and instability) make impractical
to have a global catalog that represents often an essential component in
traditional database systems. Usually, such a catalog stores information about
data, schemas and data sources. Query routing and processing are two problems
affected by the absence of a global catalog. Locating relevant data sources and
generating a close to optimal execution plan become more difficult. In this
paper, we concentrate our study on proposed solutions for the both problems.
Furthermore, selected case studies of main P2P data sharing systems are
analyzed and compared.Comment: 24 Pages, IJDM
P2P-PL: A Pattern Language to Design Efficient and Robust Peer-to-Peer Systems
To design peer-to-peer (P2P) software systems is a challenging task, because
of their highly decentralized nature, which may cause unexpected emergent
global behaviors. The last fifteen years have seen many P2P applications to
come out and win favor with millions of users. From success histories of
applications like BitTorrent, Skype, MyP2P we have learnt a number of useful
design patterns. Thus, in this article we present a P2P pattern language
(shortly, P2P-PL) which encompasses all the aspects that a fully effective and
efficient P2P software system should provide, namely consistency of stored
data, redundancy, load balancing, coping with asymmetric bandwidth,
decentralized security. The patterns of the proposed P2P-PL are described in
detail, and a composition strategy for designing robust, effective and
efficient P2P software systems is proposed.Comment: 43 pages, 27 figure
Review of Replication Schemes for Unstructured P2P Networks
To improve unstructured P2P system performance, one wants to minimize the
number of peers that have to be probed for the shortening of the search time. A
solution to the problem is to employ a replication scheme, which provides high
hit rate for target files. Replication can also provide load balancing and
reduce access latency if the file is accessed by a large population of users.
This paper briefly describes various replication schemes that have appeared in
the literature and also focuses on a novel replication technique called
Q-replication to increase availability of objects in unstructured P2P networks.
The Q-replication technique replicates objects autonomously to suitable sites
based on object popularity and site selection logic by extensively employing
Q-learning concept.Comment: 7 page
Secure and Privacy- Aware Searching in Peer-to-Peer Networks
The existing peer-to-peer networks have several problems such as fake content
distribution, free riding, white-washing and poor search scalability, lack of a
robust trust model and absence of user privacy protection mechanism. Although,
several trust management and semantic community-based mechanisms for combating
free riding and distribution of malicious contents have been proposed by some
researchers, most of these schemes lack scalability due to their high
computational, communication and storage overhead. This paper presents a robust
trust management scheme for P2P networks that utilizes topology adaptation by
constructing an overlay of trusted peers where the neighbors are selected based
on their trust ratings and content similarities. While increasing the search
efficiency by intelligently exploiting the formation of semantic community
structures by topology adaptation among the trustworthy peers, the scheme
provides the users a very high level of privacy protection of their usage and
consumption patterns of network resources. Simulation results demonstrate that
the proposed scheme provides efficient searching to good peers while penalizing
the malicious peers by increasing their search times as the network topology
stabilizes.Comment: 17 pages, 11 figures. In the Pre-proceedings of the 6th International
Workshop on Data Privacy Management (DPM) - colocated with 16th European
Symposium on Research in Computer Security (ESORICS 2011), Paper ID: 10,
September 15 - 16, 2011, Leuven, Belgiu
Performance Modeling of BitTorrent Peer-to-Peer File Sharing Networks
BitTorrent is undoubtedly the most popular P2P file sharing application on
today's Internet. The widespread popularity of BitTorrent has attracted a great
deal of attention from networking researchers who conducted various performance
studies on it. This paper presents a comprehensive survey of analytical
performance modeling techniques for BitTorrent networks. The performance models
examined in this study include deterministic models, Markov chain models, fluid
flow models, and queuing network models. These models evaluate the performance
metrics of BitTorrent networks at different regimes with various realistic
factors considered. Furthermore, a comparative analysis is conducted on those
modeling techniques in the aspects of complexity, accuracy, extensibility, and
scalability
Efficient Searching and Retrieval of Documents in PROSA
Retrieving resources in a distributed environment is more difficult than
finding data in centralised databases. In the last decade P2P system arise as
new and effective distributed architectures for resource sharing, but searching
in such environments could be difficult and time-consuming. In this paper we
discuss efficiency of resource discovery in PROSA, a self-organising P2P system
heavily inspired by social networks. All routing choices in PROSA are made
locally, looking only at the relevance of the next peer to each query. We show
that PROSA is able to effectively answer queries for rare documents, forwarding
them through the most convenient path to nodes that much probably share
matching resources. This result is heavily related to the small-world structure
that naturally emerges in PROSA.Comment: 12 pages, 3 figure
Mining frequent items in unstructured P2P networks
Large scale decentralized systems, such as P2P, sensor or IoT device networks
are becoming increasingly common, and require robust protocols to address the
challenges posed by the distribution of data and the large number of peers
belonging to the network. In this paper, we deal with the problem of mining
frequent items in unstructured P2P networks. This problem, of practical
importance, has many useful applications. We design P2PSS, a fully
decentralized, gossip--based protocol for frequent items discovery, leveraging
the Space-Saving algorithm. We formally prove the correctness and theoretical
error bound. Extensive experimental results clearly show that P2PSS provides
very good accuracy and scalability, also in the presence of highly dynamic P2P
networks with churning. To the best of our knowledge, this is the first
gossip--based distributed algorithm providing strong theoretical guarantees for
both the Approximate Frequent Items Problem in Unstructured P2P Networks and
for the frequency estimation of discovered frequent items
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